Hypertherm HPR800XD Auto Gas Rev.2 - Manual (Page 267)

Maintenance
HPR800XD Auto Gas – 806500 5-53
3. Locate dipswitch S301 on the control board (PCB3) and move switch 5 to the ON position. The switch must be
returned to its original position before cutting.
4. Measure the open circuit voltage (OCV)
Attach the test leads of a DC volt meter to the NEG terminal and the WORK terminal on the I/O board. Turn ON the
power to start the chopper test. After the contactor (CON1) closes, read the OCV which should be about 360 VDC.
• If the OCV is 0, the chopper is probably faulty. Swap chopper 1 with chopper 2 for verification. If chopper 1 is
faulty, the error code should change to 106. Replace chopper 1.
• If OCV is about 360 VDC, continue to step 5.
5. Swap current sensor 1 (CS1) with current sensor 2 (CS2). Move the sensor, but leave the power cable and the
control wiring in place.
• If the error remains on chopper 1, replace the I/O PCB.
• If the error changes to chopper 2, replace CS1.
chopper 3, 2, or 4 failure
1. Swap the current sensor for the chopper that failed with the current sensor for the next chopper in sequence.
• If the error moves to the next chopper in sequence, replace the current sensor for the chopper that failed.
• If the error remains on the original chopper, continue to step 2.
2. Swap the chopper that failed with the next chopper in sequence. Remember that the chopper test sequence is
chopper 1, chopper 3, chopper 2, and chopper 4.
• If the error moves to the position where you installed the chopper that failed, replace the chopper.
• If the error remains on the original chopper, the issue is with the control board or wiring.
Note: Return switch 5 on S301 to the OFF position before returning to normal cutting operations.